Xircom, Modem, models:

100Base-TX	Specifications
OP-720-69001 - Xircom RealPort CardBus Ethernet 10/100	User Manual
OP-720-69001 - Xircom RealPort CardBus Ethernet...	User Manual
RM56V1	User Manual
RealPort CardBus Ethernet 10/100 + Modem 56	User Manual
RealPort REM56G-100BTX	Specifications